基于AQUA/MODIS的FY-4A/AGRI传感器热红外通道交叉辐射定标方法  

Cross-calibration for Thermal Infrared Channels of FY-4A/AGRI Sensor Based on AQUA/MODIS

作　　者：刘佳欣 高彩霞 杨治纬 邱实 赵永光 马灵玲 钱永刚 LIU Jiaxin;GAO Caixia;YANG Zhiwei;QIU Shi;ZHAO Yongguang;MA Lingling;QIAN Yonggang(Key Laboratory of Quantitative Remote Sensing Information Technology,Aerospace Information Research Institute,Chinese Academy of Sciences,Beijing 100094,China;School of Resources and Environment,University of Chinese Academy of Science,Beijing 100049,China;School of Optoelectronics,University of Chinese Academy of Science,Beijing 100049,China)

机构地区：[1]中国科学院空天信息创新研究院中国科学院定量遥感信息技术重点实验室,北京100094 [2]中国科学院大学资源与环境学院,北京100049 [3]中国科学院大学光电学院,北京100049

出　　处：《无线电工程》2021年第12期1373-1381,共9页Radio Engineering

基　　金：科技部国家重点研发计划课题(2018YFB0504804)。

摘　　要：风云四号卫星(FengYun-4A Satellite,FY-4A)是我国新一代静止气象卫星,搭载多通道扫描成像辐射计(Advanced Geostationary Radiation Imager,AGRI)等多种观测仪器。为检验AGRI传感器热红外通道的辐射观测精度,基于AQUA卫星搭载的中分辨率成像光谱仪(Moderate Resolution Imaging Spectroradiometer,MODIS)对FY-4A/AGRI传感器热红外通道开展交叉辐射定标。利用4A/OP辐射传输模型模拟数据计算MODIS和AGRI数据对的光谱匹配因子,提取参考载荷(MODIS)研究区目标观测辐亮度值,并经过空间、时间、光谱和角度匹配后,推算相应通道待定标载荷(AGRI)TOA辐亮度参考值,并与其研究区目标观测值进行对比分析,计算参考值和观测值的相对差异,以此来验证待定标载荷辐射观测值的准确性。结果表明,FY-4A/AGRI热红外通道定标后的辐亮度值相对差异在±10%以内,随着观测天顶角(Viewing Zenith Angle,VZA)差异减小,辐亮度值相对差异较小。当VZA差异小于10°时,辐亮度值相对差异基本保持在±5%以内。The FY-4A satellite is a new generation of geostationary meteorological satellites in China,equipped with multiple observation instruments such as Advanced Geostationary Radiation Imager(AGRI).In order to validate the radiation observation accuracy of thermal infrared channel of the AGRI sensor,the thermal infrared channels of FY-4A/AGRI are cross-calibrated with the Moderate Resolution Imaging Spectroradiometer(MODIS)onboard AQUA satellite.The 4A/OP radiative transfer model is used to calculate the spectral matching factor of MODIS and AGRI data pairs.After that,the observed radiance from MODIS over the study area is extracted,and the reference radiance for AGRI TOA are estimated from the MODIS observation as reference value after spatial,temporal,spectral,and angular matching.And the comparative analysis is performed with the observed value of the research zone.Then the relative difference between the reference and the observed radiance is calculated to validate the radiometric accuracy of AGRI.The results show that the relative differences for the thermal infrared channels of FY-4A/AGRI after calibration are within±10%.As the difference of the viewing zenith angle(VZA)decreases,the relative radiance difference become smaller.When the VZA differences are less than 10°,the relative radiance difference is within±5%.

关 键 词：交叉辐射定标 4A/OP辐射传输模型 FY-4A 中分辨率成像光谱仪 光谱匹配因子 

分 类 号：TP732.2[自动化与计算机技术—检测技术与自动化装置]